A valveless micropump based on parallel dual-vibrator and its pumping method

Abstract

This invention discloses a valveless micropump based on parallel dual vibrators and a pumping method. The valveless micropump includes a stacked vibrating element, a diaphragm layer, a flow channel layer, and a resonant layer. Both the diaphragm layer and the resonant layer have two spaced gaps forming a vibrator structure with fixed ends and a free middle. The two side edges of the vibrator structure are aligned with the two side walls of the pumping chamber. The vibrating element drives the diaphragm layer and the resonant layer to perform synchronous, opposite-directional wave-like vibrations. The vibrating diaphragm layer and the resonant layer periodically separate and contact at one or more discontinuous flow-limiting points. These discontinuous flow-limiting points are arranged along the length of the pumping chamber. Some or all of the discontinuous flow-limiting points are provided with flow passage structures communicating with the external environment.

Description

Technical Field

[0001] This invention belongs to the field of piezoelectric micropump technology, specifically relating to a valveless micropump based on parallel dual vibrating plates and a pumping method. Background Technology

[0002] As a type of micro-device that strongly couples multiple disciplines such as materials, structure, fluid, electronics, and process, the micro piezoelectric pump has advantages such as small size, low power consumption, high specific back pressure, large specific flow rate, high speed response, and high flow accuracy. It has a wide range of applications in the fields of medical devices and semiconductor thermal management, and is particularly suitable for wearable and portable medical devices and ultra-thin micro-space heat dissipation management applications.

[0003] The application of piezoelectric micropumps in air cooling primarily lies in their role as key components in the cooling systems of electronic devices, especially in the thermal management of high-power, miniaturized electronic equipment. Piezoelectric micropumps utilize the piezoelectric effect to generate fluid flow, offering advantages such as small size, low power consumption, precise control, and high reliability, making them ideal for integration into portable and microelectronic devices. They can drive coolant to circulate through microchannels or heat exchangers within electronic devices, effectively dissipating heat and maintaining the optimal operating temperature of electronic components.

[0004] In the field of heat dissipation, micropumps fabricated using the synthetic jet principle exhibit significantly higher heat dissipation efficiency than traditional micropumps. Conventional pumps create a flow field with a stable boundary layer, where heat exchange with the external fluid occurs only through this layer, resulting in low heat transfer efficiency. In contrast, synthetic jet micropumps drive a flow field consisting of vortex pairs or vortex rings, exhibiting pulsating and entrainment characteristics. The high-frequency pulsating flow field has an unstable boundary, allowing the low-temperature fluid to directly contact the high-temperature wall surface, greatly improving heat transfer efficiency. Furthermore, the vortex rings and vortex pairs ejected by the synthetic jet pump continuously entrain low-temperature fluid from the environment during rotation, increasing the net fluid flow rate and further enhancing heat transfer efficiency. Therefore, heat transfer based on synthetic jet-driven flow fields is 2-3 times more efficient than conventional fans or pumps, featuring low net flow rate, low power consumption, and high heat transfer capacity, making it a promising candidate for applications in micro-space heat dissipation.

[0005] The main drawbacks of the existing technology are as follows:

[0006] 1. The structure of a typical air-cooled piezoelectric micropump is generally closed, that is, the internal vibration cavity is closed. Therefore, when the oscillator vibrates, it will be restricted by the closed vibration cavity, resulting in a smaller amplitude of the oscillator. A smaller amplitude of the oscillator will directly lead to a smaller flow rate of the piezoelectric micropump.

[0007] 2. In a typical air-cooled piezoelectric micropump, the oscillator is generally circular, meaning the piezoelectric micropump is rectangular in shape. The internal piezoelectric oscillator and cavity are circular, resulting in low internal volume utilization. Furthermore, when the circular piezoelectric oscillator and cavity are arrayed, some of the volume is not utilized, leading to a smaller volume change rate, making it unsuitable for arraying.

[0008] 3. Conventional air-cooled piezoelectric micropumps typically have vertical airflow inlet and outlet, dissipating heat through vertical flow field pulses. However, when synthetic jet technology is used for cooling, at least 100mm of flow field evolution distance must be reserved in the outlet direction. When this space is less than 100mm, vortices and vortex rings cannot be generated or evolve sufficiently, resulting in virtually no flow and no cooling effect. Therefore, vertical air cooling is often extremely limited in the thickness direction when applied to ultra-thin space cooling applications.

[0009] 4. Existing side-discharge air-cooled piezoelectric micropumps require a valve to control the airflow. First, the addition of a valve makes the entire system structure more complex, increasing the difficulty of design and manufacturing. Second, the valve is prone to mechanical wear during frequent opening and closing, leading to a decrease in sealing performance or even failure. Third, the thickness of an air-cooled piezoelectric micropump with a valve cannot be very thin due to the presence of the valve.

[0010] For example, Chinese patent CN118622665A discloses a "Piezoelectric Pump, Micro Pump Assembly and Electronic Device", which specifically discloses the following: "A circular through hole is provided in the middle of the cavity cover 120, and an air outlet 122 is provided on one side, which is connected to the side of the through hole. In this embodiment, the piezoelectric pump 100 is formed by setting a pump assembly 110 and a cover plate 150, with the pump assembly 110 and the cover plate 150 located at opposite ends of the through hole to seal and cover both ends of the through hole to form a pump chamber 121. The cover plate 150 can be a metal plate similar to the vibrator plate 113, and the vibrator plate 113 and the cover plate 150 can be connected to the cavity cover 120 by bonding. During operation, as the vibrator plate 113 agitates, the cover plate 150 can agitate accordingly" (paragraph 0038 of the prior art specification). Referring to the prior art... Figures 2 to 4 As can be seen, the internal cavity of the piezoelectric pump provided by this patent is closed. When the oscillator vibrates, the internal cavity of the piezoelectric pump restricts the amplitude, resulting in insufficient amplitude and inability to generate a large flow rate.

[0011] For example, Chinese patent CN111828289B discloses a "Micropump MEMS Device for Moving or Jetting Fluid," which specifically discloses the following: "A piezoelectric element is fixed on the back of a vibrating plate to form a single membrane. When the piezoelectric element is biased by an AC voltage, the single membrane bends in opposite directions through alternating motion, decreasing and increasing the volume of the central chamber. These volume changes alternately cause fluid to be drawn in from the supply path inlet and discharged through the jet outlet in an alternating manner. Therefore, with this structure, a small amount of fluid can be moved precisely at a rate greater than 0.2 mL / min: thus, a micro fan can be used to cool electronic devices using air. However, it is desirable to have a micropump device capable of moving fluid volumes that vary from very low to high values ​​with high precision" (paragraphs 0004 to 0006 of the prior art specification). It can be seen that the prior art is a jet-type air-cooled micropump, whose specific operation is as follows: "Each actuator element 5 includes a fluid inlet path 10 and an outlet opening 11. In the illustrated embodiment, The fluid inlet path 10 opens on the first main surface 3A through the inlet opening 12. The outlet opening 11 is arranged on the second main surface 3B, with one outlet opening 11 for each actuator element 5. The inlet opening 12 can be connected to an external fluid circuit (not shown), for example, to draw in liquid or gas contained in a reservoir, or directly connected to the external environment, for example, to draw in ambient air. Similarly, depending on the intended application, the outlet opening 11 can be connected to an external fluid circuit (not shown), or connected to the outside (paragraph 0021 of the prior art). It can be seen that the prior art draws in fluid through the inlet on the lower surface and ejects fluid through the outlet on the upper surface. The individual MEMS pump in this micropump MEMS device is not only relatively thick, but also uses a circular oscillator. The volume change rate of a single pump is small (the oscillator cavity accounts for a small proportion in the micropump), and its flow rate is very small. Therefore, it is a micropump MEMS device composed of multiple MEMS pumps in an array, resulting in a large overall volume in order to achieve a large flow rate. Moreover, there is some volume waste in the process of arraying.

[0012] For example, Chinese patent CN116857159A discloses a "flow guiding structure and valveless piezoelectric micropump," which specifically discloses the following: "A spiral Tesla valve 111 is provided on the first side of the body 11. The body 11 is provided with a first opening 112 and a second opening 113 spaced apart. The first opening 112 is connected to the first end of the Tesla valve 111, and the second opening 113 is connected to the second end of the Tesla valve 111. The Tesla valve 111 has a forward flow direction from the first opening 112 to the second opening 113 and a reverse flow direction from the second opening 113 to the first opening 112" (previous reference document). Paragraph 0055 of the specification states that "Since the Tesla valve 111 is spirally arranged on one side of the body 11, the Tesla valve 111 can maintain a longer path while utilizing the characteristics of the spiral structure to reduce the volume and space occupied by the body 11, thus achieving the design objective of a small-volume flow guiding structure 10. For example, if a Tesla valve 111 of length L needs to be designed, a straight Tesla valve 111 would result in a longer body 11. In contrast, the spiral shape of the Tesla valve 111 in this embodiment of the invention is beneficial for reducing the design size of the body 11" (paragraph 0057 of the prior art specification). Referring further to the prior art... Figures 4 to 6 As can be seen, in order to guide the flow, a Tesla valve is set up in the comparative document. That is, "by changing the shape of the pipe and utilizing the fluid's own flow inertia, not only can the backflow of the fluid be reduced, which is conducive to the directional flow of the fluid in the Tesla valve, but also a larger fluid delivery volume can be achieved. It can also reduce the overall space occupied by the flow guiding structure and achieve the design purpose of a small-volume flow guiding structure" (paragraph 0023 of the specification in the comparative document). It can be seen that although the Tesla valve structure can play a role in guiding the flow, the structure of the Tesla valve itself is relatively complex, which leads to an increase in its thickness. Furthermore, the structure of the piezoelectric pump itself is also more complex, and the manufacturing process is also more complicated. Summary of the Invention

[0013] The purpose of this invention is to solve the problems of large thickness and small amplitude of existing air-cooled piezoelectric micropumps, and to provide a valveless micropump and pumping method based on parallel double vibrators. By setting extremely narrow gaps on both sides of the vibrator, the interior of the valveless micropump forms intermittent flow-limiting points with periodic conduction and flow restriction. Since the valve structure is eliminated, the overall thickness of the valveless micropump of this invention is reduced, and the presence of gaps makes the amplitude of the valveless micropump of this invention larger.

[0014] In a first aspect, the present invention provides a valveless micropump based on parallel dual vibrators, comprising a stacked vibrating element, a diaphragm layer, a flow channel layer, and a resonant layer; the opposing sides of the diaphragm layer and the resonant layer, together with the sidewall of the groove within the flow channel layer, form a pump chamber. Both the diaphragm layer and the resonant layer have two spaced gaps forming a vibrator structure with fixed ends and a free middle section. The vibrator structure corresponds to the position of the pump chamber.

[0015] The vibrating element drives the diaphragm layer and resonant layer to perform synchronous, opposite-directional wave-like vibrations. The vibrating diaphragm layer and resonant layer periodically move away from and towards each other at one or more discontinuous flow-limiting points. These discontinuous flow-limiting points are arranged along the length of the pump chamber. Some or all of these discontinuous flow-limiting points are equipped with flow passage structures that communicate with the external environment.

[0016] Preferably, the two side edges of the diaphragm structure are aligned with the two side walls of the pump chamber.

[0017] Preferably, the width of the slit is 1 to 5 micrometers, which can prevent fluid leakage.

[0018] Preferably, the vibrating element is located entirely between the two gaps in the diaphragm layer.

[0019] Preferably, both the vibrating element and the diaphragm structure are rectangular. The vibrating element is fixed to the diaphragm structure.

[0020] Preferably, there are three intermittent flow-limiting points and three flow-passing structures. Each flow-passing structure is arranged sequentially on the side of the flow channel layer. The relative approach and separation of the intermittent flow-limiting points on both sides and the intermittent flow-limiting point in the middle are asynchronous.

[0021] Preferably, the diaphragm layer, the flow channel layer, and the resonant layer are all provided with stress joints surrounding the pump chamber.

[0022] Preferably, the flow channel layer has a fluid channel on its side. The fluid channel intersects with three flow structures in a cross shape. The diaphragm layer has multiple flow holes on its side. Each flow hole communicates with a different position of the fluid channel. Each flow hole is staggered from the three flow structures.

[0023] Preferably, a rectifier layer is also included. The rectifier layer is connected to the side of the resonant layer opposite to the flow channel layer. One or more sets of aligned through holes are formed on the resonant layer and the rectifier layer to create a flow passage structure that communicates with the external environment. The groove structure on the resonant layer and the rectifier layer together form an output chamber.

[0024] Preferably, both ends of the output chamber are connected to the external environment through flow holes formed in the vibrating element, diaphragm layer, and flow channel layer.

[0025] Preferably, there are three intermittent flow restriction points; each of the three intermittent flow restriction points is provided with a flow passage structure.

[0026] Preferably, the number of intermittent flow-limiting points is three; the number of flow passage structures is one. The flow passage structure is aligned with the intermittent flow-limiting point located in the middle.

[0027] Preferably, the vibration element includes actuating plates and reinforcing plates stacked together.

[0028] Secondly, the present invention provides a pumping method using the aforementioned valveless micropump. The valveless micropump has three intermittent flow-limiting points. The pumping method includes: introducing a periodic electrical signal into the vibrating element to drive the diaphragm layer and resonant layer to perform synchronous, opposite-directional wave-like vibrations; the intermittent flow-limiting points on both sides and the intermittent flow-limiting point in the middle alternately moving away from and towards each other; and the flow passage structure corresponding to each intermittent flow-limiting point periodically drawing air inward or pumping air outward.

[0029] The beneficial effects of this invention are:

[0030] 1. This invention creates two extremely narrow slits on the diaphragm and resonant layers, forming aligned rectangular diaphragm structures on both layers. These rectangular diaphragm structures, fixed at both ends and free in the middle, can undergo wave-like vibrations. This causes the diaphragm and resonant layers to periodically move away from and towards each other at specific locations, resulting in periodic increases and decreases in the flow resistance of the flow passage structure. This acts similarly to a valve, eliminating the need for a complex valve body structure, simplifying the micropump structure, reducing its thickness, and facilitating its integration into micro-devices and mobile devices.

[0031] 2. In this invention, the rectangular diaphragm structure formed by two extremely narrow gaps is free in the middle, which expands the amplitude of the diaphragm structure. Moreover, the vibration directions of the rectangular diaphragm structure on the diaphragm layer and the resonant layer are opposite, which further increases the volume change rate of the pump chamber and improves the flow rate of the valveless micropump.

[0032] 3. In this invention, both the diaphragm structure and the vibrating element are rectangular, which enables the acquisition of rectangular piezoelectric micropumps with higher utilization rates. Rectangular piezoelectric micropumps are also advantageous for arraying.

[0033] 4. When the present invention adopts the side air outlet scheme, based on the three discontinuous flow limiting points, the principle of synthetic jet can be used to form vortex pairs and vortex rings in the side flow structure, thereby increasing the flow rate of the valveless micro pump. Attached Figure Description

[0034] Figure 1 This is a front view of the valveless micropump provided in Embodiment 1 of the present invention.

[0035] Figure 2 This is a perspective view of the valveless micropump provided in Embodiment 1 of the present invention.

[0036] Figure 3 This is a schematic diagram of the structure of the first slit in the valveless micropump provided in Embodiment 1 of the present invention. Figure 2 (Enlarged view of part A in the middle).

[0037] Figure 4 This is an exploded view of the valveless micropump provided in Embodiment 1 of the present invention.

[0038] Figure 5 This is a schematic diagram of the fluid output process of the valveless micropump provided in Embodiment 1 of the present invention.

[0039] Figure 6 This is a schematic diagram of the fluid intake process of the valveless micropump provided in Embodiment 1 of the present invention.

[0040] Figure 7 This is a perspective view of the valveless micropump provided in Embodiment 2 of the present invention.

[0041] Figure 8 This is an exploded view of the valveless micropump provided in Embodiment 2 of the present invention.

[0042] Figure 9 This is a bottom view of the valveless micropump provided in Embodiment 2 of the present invention.

[0043] Figure 10 This is a schematic diagram of the fluid intake process of the valveless micropump provided in Embodiment 2 of the present invention.

[0044] Figure 11 This is a schematic diagram of the fluid output process of the valveless micropump provided in Embodiment 2 of the present invention.

[0045] Figure 12 This is an exploded view of the valveless micropump provided in Embodiment 3 of the present invention.

[0046] Figure 13 This is a schematic diagram of the fluid intake process of the valveless micropump provided in Embodiment 3 of the present invention.

[0047] Figure 14 This is a schematic diagram of the fluid output process of the valveless micropump provided in Embodiment 3 of the present invention.

[0048] Figure 15 This is an exploded view of the valveless micropump provided in Embodiment 4 of the present invention.

[0049] Figure 16 This is a schematic diagram of the array pump structure provided in Embodiment 4 of the present invention.

[0050] In the diagram, 100 is the actuating plate; 200 is the reinforcing plate; 300 is the diaphragm layer; 310 is the first gap; 320 is the flow hole; 330 is the first flow hole; 400 is the flow channel layer; 410 is the first parallel flow structure; 420 is the second parallel flow structure; 430 is the third parallel flow structure; 440 is the fixing part; 450 is the flow part; 460 is the fluid channel; 500 is the resonant layer; 510 is the second gap; 520 is the internal flow hole; 530 is the third flow hole; 600 is the rectifying layer; 610 is the first external flow hole; 620 is the second external flow hole; 630 is the third external flow hole; 640 is the fluid channel; 700 is the pump chamber; 800 is the output chamber; and 900 is the stress joint. Detailed Implementation

[0051] The present invention will be further described below.

[0052] In the following embodiments, the width side of the valveless micropump is defined as the front-to-back direction, the length side is defined as the left-to-right direction, and the thickness direction of the valveless micropump is defined as the up-to-down direction.

[0053] Example 1

[0054] This embodiment provides a valveless micropump with side-discharge airflow based on parallel dual-vibrating plates.

[0055] like Figure 1 , Figure 2 , Figure 3 and Figure 4 As shown, a valveless micropump based on parallel dual-vibrator plates includes an actuator plate 100, a reinforcing plate 200, a diaphragm layer 300, a flow channel layer 400, and a resonant layer 500 stacked sequentially from top to bottom. A plurality of flow passage structures are provided on one side of the valveless micropump. After the actuator plate 100, reinforcing plate 200, diaphragm layer 300, flow channel layer 400, and resonant layer 500 are connected, fluid is drawn in or pumped out from the flow passage structures on one side of the valveless micropump based on parallel dual-vibrator plates through the vibration of the actuator plate 100.

[0056] Figure 1 This is a front view of a valveless micropump based on parallel dual vibrating plates according to the present invention, which specifically shows the components of the valveless micropump in this embodiment.

[0057] The flow channel layer 400 has a rectangular groove running vertically through it. The opposite sides of the diaphragm layer 300 and the resonant layer 500, together with the sidewalls of the rectangular groove within the flow channel layer 400, form a pump chamber. The pump chamber has a rectangular cross-section. The side of the flow channel layer 400 has a fluid channel 460 and three sequentially spaced flow structures: a first parallel flow structure 410, a second parallel flow structure 420, and a third parallel flow structure 430. The fluid channel 460 extends along the length of the pump chamber; the three flow structures are arranged sequentially along the length of the pump chamber. The fluid channel 460 intersects the three flow structures in a cross shape. The outer ends of the three flow structures communicate with the external environment. The inner ends of the three flow structures communicate with the pump chamber.

[0058] The pump chamber is divided into three interconnected working areas along its length: two suction areas and a pump outlet area located between the two suction areas. The two suction areas are aligned with the first parallel flow structure 410 and the third parallel flow structure 430, respectively. The pump outlet area is aligned with the second parallel flow structure 420.

[0059] The actuator 100 is fixedly connected to the reinforcing plate 200, which is fixed at the center of the upper surface of the diaphragm layer 300. The lower surface of the diaphragm layer 300 is fixedly connected to the upper surface of the flow channel layer 400. The lower surface of the flow channel layer 400 is fixedly connected to the upper surface of the resonant layer 500. When the actuator 100 vibrates through the piezoelectric effect, it drives the reinforcing plate 200, which in turn drives the diaphragm layer 300. The resonant layer 500 vibrates in the opposite direction to the diaphragm layer 300. Thus, the actuator 100, the reinforcing plate 200, the diaphragm layer 300, and the resonant layer 500 vibrate together in coordination.

[0060] Figure 2 This is an isometric diagram of a valveless micropump based on parallel dual-vibrator plates according to the present invention, which specifically illustrates the connection relationship and composition structure of the valveless micropump provided in this embodiment, such as... Figure 2 As shown, in this embodiment, all components of the valveless micropump except for the actuator 100 are made of stainless steel; in some other embodiments, the other components of the valveless micropump except for the actuator 100 may also be made of carbon fiber.

[0061] The actuator 100, reinforcing plate 200, diaphragm layer 300, flow channel layer 400, and resonant layer 500 are all rectangular; the actuator 100 and reinforcing plate 200 are the same size and shape; the diaphragm layer 300, flow channel layer 400, and resonant layer 500 are the same size and shape. The area of ​​the actuator 100 and reinforcing plate 200 is smaller than the area of ​​the diaphragm layer 300, flow channel layer 400, and resonant layer 500; the actuator 100 and reinforcing plate 200 are fixedly connected to the central part of the diaphragm layer 300. Figure 1As shown, the diaphragm layer 300 has the thinnest thickness. The sum of the thicknesses of the actuator plate 100 and the reinforcing plate 200 is greater than the thickness of the diaphragm layer 300, but less than the thickness of the resonant layer 500. The thickness of the resonant layer 500 is less than the thickness of the flow channel layer 400.

[0062] Two first slits 310 are symmetrically arranged vertically through the diaphragm layer 300. The first slits 310 extend along the length of the diaphragm layer 300 and are not connected to either end edge of the diaphragm layer 300. The two first slits 310 are spaced apart along the width of the diaphragm layer 300 and are aligned with the left and right side walls of the pump chamber within the flow channel layer 400, respectively. The two first slits 310 are symmetrical about the centerline of the diaphragm layer 300.

[0063] The diaphragm layer 300 has multiple flow holes 320 on its side. Each flow hole 320 is aligned with and connected to the corresponding fluid channel 460. Each flow hole 320 is staggered from the three flow structures.

[0064] In some embodiments, the flow hole 320 has an oblong shape, i.e., a rectangle with rounded edges on both sides; the number of flow holes 320 is six; the six flow holes 320 include two large flow holes 320 of the same area and four small flow holes 320 of the same area; the two large flow holes 320 of the same area are respectively located between the first parallel flow structure 410 and the second parallel flow structure 420, and between the second parallel flow structure 420 and the third parallel flow structure 430; the four small flow holes 320 of the same area are respectively located on the side of the first parallel flow structure 410 and the third parallel flow structure 430 away from the second parallel flow structure 420.

[0065] Figure 3 This is an enlarged view of point A in the isostatic diagram of a valveless micropump based on parallel dual vibrating plates according to the present invention. Figure 4 This is an exploded view of a valveless micropump based on parallel dual vibrators according to the present invention, which specifically shows the specific structure of the slit in the valveless micropump in this embodiment; in this embodiment, as... Figure 3 and Figure 4 As shown, the resonant layer 500 has two second slits 510 that penetrate vertically through the resonant layer 500. The two first slits 310 and the two second slits 510 are aligned. Both the first slits 310 and the second slits 510 are extremely narrow and elongated strips; the cross-sectional shapes of the first slits 310 and the second slits 510 are the same, that is, their lengths and widths are the same; since the thickness of the diaphragm layer 300 is less than the thickness of the resonant layer 500, the thicknesses of the first slits 310 and the second slits 510 are different.

[0066] Because the flow channel layer 400 has a hollow pump chamber inside, there is no obstruction between the first gap 310 and the second gap 510, and the valveless micro-pump is completely connected vertically. The length of the first gap 310 and the second gap 510 is greater than the length of the actuator plate 100 and the reinforcing plate 200, and less than the length of the diaphragm layer 300, the flow channel layer 400 and the resonant layer 500. The width of the first gap 310 and the second gap 510 is much smaller than the overall width of the diaphragm layer 300 and the resonant layer 500. In this embodiment, the width of the first gap 310 and the second gap 510 is 2 micrometers.

[0067] Two first slits 310 penetrating the diaphragm layer 300 create a first diaphragm structure in the middle of the diaphragm layer 300, which is fixed at both ends and free in the middle, and has a sheet-like shape. Two second slits 510 penetrating the resonant layer 500 create a second diaphragm structure in the middle of the resonant layer 500, which is fixed at both ends and free in the middle, and has a sheet-like shape. The first diaphragm structure, the second diaphragm structure, and the pump chamber are aligned with each other and have the same cross-section.

[0068] The first gap 310 and the second gap 510 respectively create free edges on both sides of the first and second vibrating plate structures, thereby effectively increasing the amplitude of the valveless micropump during vibration and improving the pump air flow rate. Simultaneously, the first and second vibrating plate structures undergo opposite wave-like vibrations during operation, forming three sequentially arranged discontinuous flow-limiting points in the pump air chamber, namely the first discontinuous flow-limiting point, the second discontinuous flow-limiting point, and the third discontinuous flow-limiting point. In this embodiment, the discontinuous flow-limiting points are not specific structural descriptions, but rather names of locations that naturally approach and form flow-limiting points during vibration.

[0069] In some other embodiments, the number of intermittent flow-limiting sites is a number other than three, such as 1, 2, 4, 5, or 6.

[0070] As the opposing sides of the first and second vibrating plate structures periodically move away from and towards each other at the discontinuous flow-limiting points, the movement of the first and third discontinuous flow-limiting points moving away and towards each other is synchronous (with the same phase); the movement of the first and second discontinuous flow-limiting points moving away and towards each other is asynchronous (with a phase difference of 180°). The three discontinuous flow-limiting points are aligned with the three flow passage structures respectively; when the gap at the discontinuous flow-limiting point decreases (the diaphragm layer 300 and the resonant layer 500 move closer to each other), the flow resistance of the corresponding flow passage structure increases significantly, thereby realizing automatic control of the gas flow direction in the valveless micropump. Therefore, the pump chamber at the three discontinuous flow-limiting points can periodically conduct and limit flow with vibration. Due to the vibration characteristics of the actuator 100, reinforcing plate 200, diaphragm layer 300, and resonant layer 500, there is a 180° phase difference between the flow passage and flow-limiting states of the discontinuous flow-limiting points on both sides and the discontinuous flow-limiting point in the middle.

[0071] Figure 4 This is an exploded view of a valveless micropump based on parallel dual-vibrator plates according to the present invention, which specifically shows the structure of each layer in this embodiment. In this embodiment, as shown... Figure 4 As shown, the flow channel layer 400 includes a fixed part 440 and a flow part 450. The flow part 450 is not connected to the fixed part 440, but is connected and fixed to the diaphragm layer 300 above the flow channel layer 400 and the resonant layer 500 below the flow channel layer 400. A flow passage structure is formed between the flow part 450 and the fixed part 440.

[0072] In this embodiment, all flow passage structures are located on the same side of the flow channel layer 400; the other side of the flow channel layer 400 is completely closed, that is, the porous side-outlet valveless micro-pump in this embodiment enters and exits air from the same side.

[0073] In some embodiments, the diaphragm layer 300, the flow channel layer 400, and the resonant layer 500 are provided with through-structure stress seams 900. The stress seams 900 surround the pump chamber but are not connected to it. The stress seams 900 employ an intermittent surrounding structure, meaning multiple stress seams 900 are sequentially and discontinuously connected to form a ring around the pump chamber (with intervals between adjacent stress seams 900), to avoid completely isolating the internal and external regions of the diaphragm layer 300, the flow channel layer 400, and the resonant layer 500. The stress seams 900 disperse the stress of the diaphragm layer 300, the flow channel layer 400, and the resonant layer 500 around each stress seam 900, preventing excessive stress concentration at the through-hole structures and thus avoiding excessive local stress. Therefore, the stress seams 900 help improve the stability of the valveless micropump during long-term operation and extend its service life.

[0074] The working process of the valveless micropump based on parallel dual-vibrator provided in this embodiment is as follows: a periodic electrical signal of a preset frequency is introduced into the actuator 100, causing the diaphragm layer 300 and the resonant layer 500 to vibrate in opposite directions periodically, driving gas to flow in from the first parallel flow structure 410 and the third parallel flow structure 430, and to flow out from the second parallel flow structure 420, thereby realizing continuous pumping action.

[0075] Each vibration cycle of the actuator plate 100 is divided into a fluid output process and a fluid intake process.

[0076] Figure 5 This is a vibration principle diagram of the valveless micropump provided in this embodiment during the fluid output process, referred to... Figure 5The fluid output process is as follows: When the middle part of the actuator plate 100 vibrates upward through the piezoelectric effect, it drives the middle part of the reinforcing plate 200 to vibrate upward. The actuator plate 100 and the reinforcing plate 200 drive the middle part of the diaphragm layer 300 below (corresponding to the second discontinuous flow limiting point) to vibrate upward. The middle part of the resonant layer 500 below the diaphragm layer 300 (corresponding to the second discontinuous flow limiting point) vibrates downward. At this time, the volume of the middle part of the pump chamber (corresponding to the second discontinuous flow limiting point) increases; while the two sides of the diaphragm layer 300 (corresponding to the first and third discontinuous flow limiting points) bend downward under the action of the actuator plate 100 and the reinforcing plate 200, and the two sides of the resonant layer 500 (corresponding to the first and third discontinuous flow limiting points) bend upward; the pump The volume of the two sides of the air chamber (corresponding to the first and third discontinuous flow limiting points) decreases and the pressure increases. At the same time, the diaphragm layer 300 and the resonant layer 500 move closer to each other at the first and third discontinuous flow limiting points to limit the flow, which increases the flow resistance at the first parallel flow structure 410 and the third parallel flow structure 430. Under the action of the pressure difference, the fluid flows from both sides of the pump air chamber to the middle (i.e., from the first and third discontinuous flow limiting points to the second discontinuous flow limiting point), and then flows out at high speed through the second parallel flow structure 420, thereby realizing the outward output of the fluid. After the flow resistance at the first and third discontinuous flow limiting points increases, only a small amount of fluid is drawn in or flows out from the first parallel flow structure 410 and the third parallel flow structure 430.

[0077] Figure 6 This is a vibration principle diagram of the valveless micropump provided in this embodiment during the fluid suction process, referred to... Figure 6 The fluid intake process is as follows: When the middle part of the actuator plate 100 vibrates downward through the piezoelectric effect, it drives the middle part of the reinforcing plate 200 to vibrate downward. The middle parts of the actuator plate 100 and the reinforcing plate 200 drive the middle part of the diaphragm layer 300 below (corresponding to the second discontinuous flow limiting point) to vibrate downward. The middle part of the resonant layer 500 below the diaphragm layer 300 (corresponding to the second discontinuous flow limiting point) vibrates upward. At this time, the volume of the middle part of the pump chamber (corresponding to the second discontinuous flow limiting point) decreases; while the two sides of the diaphragm layer 300 (corresponding to the first and third discontinuous flow limiting points) bend upward under the action of the two sides of the actuator plate 100 and the reinforcing plate 200, corresponding to the resonant layer 500. The two sides of 0 (corresponding to the first and third discontinuous flow limiting points) bend downwards; the volume of the two sides of the pump chamber (corresponding to the first and third discontinuous flow limiting points) increases and the pressure decreases; at the same time, the diaphragm layer 300 and the resonant layer 500 approach each other at the second discontinuous flow limiting point, which increases the flow resistance of the second parallel flow structure 420; under the action of pressure difference, the external fluid of the valveless micropump flows into the pump chamber from the first parallel flow structure 410 and the third parallel flow structure 430 under the action of pressure difference, thereby realizing the inward suction of fluid; after the flow resistance of the second discontinuous flow limiting point increases, only a small amount of fluid is sucked in or flows out from the second parallel flow structure 420.

[0078] Example 2

[0079] This embodiment provides a valveless micropump with vertical air outlet based on parallel dual vibrators; the valveless micropump has a rectangular structure, with the width side extending in the front-to-back direction and the length side extending in the left-to-right direction.

[0080] This embodiment provides a valveless micropump based on parallel dual-vibrator plates, which is largely the same as Embodiment 1, except that the valveless micropump provided in this embodiment also includes a rectifier layer 600. The flow channel layer 400 has no flow passage structure on its side; both the resonant layer 500 and the rectifier layer 600 have three vertically arranged flow passages in their middle sections. The mutually aligned flow passages on the resonant layer 500 and the rectifier layer 600 form a flow passage structure connecting to the external environment.

[0081] like Figure 7 , Figure 8 and Figure 9 As shown, this embodiment provides a valveless micropump based on parallel dual-plate diaphragms, comprising, from top to bottom, an actuator plate 100, a reinforcing plate 200, a diaphragm layer 300, a flow channel layer 400, a resonant layer 500, and a rectifier layer 600. The areas of the actuator plate 100 and the reinforcing plate 200 are smaller than those of the diaphragm layer 300, the flow channel layer 400, and the resonant layer 500.

[0082] The flow channel layer 400 has a rectangular groove running vertically through it. The opposite sides of the diaphragm layer 300 and the resonant layer 500, together with the sidewall of the rectangular groove in the flow channel layer 400, form a pump chamber 700. The resonant layer 500 and the groove structure on the upper surface of the rectifier layer 600 together form an output chamber 800.

[0083] In this embodiment, one or more flow holes aligned with each other are provided on the diaphragm layer 300, the flow channel layer 400, and the resonant layer 500. In some preferred embodiments, the flow holes are located at the left and right ends of the diaphragm layer 300, the flow channel layer 400, and the resonant layer 500, with two at each end, i.e., four flow holes are provided in each layer. The diaphragm layer 300 has four first flow holes 330, the flow channel layer 400 has four second flow holes 410, and the resonant layer 500 has four third flow holes 530. The flow holes have the same overall area and are continuous. The groove structure on the rectifier layer 600 has two fluid channels 640 at each end. The four fluid channels 640 are aligned with and connected to the four third flow holes 530. The fluid channels 640 are rectangles with rounded chamfers at the edges, completely surrounding the flow holes. Each flow hole and fluid channel 640 allows the two ends of the output chamber 800 to communicate with the external environment.

[0084] The rectifier layer 600 has three vertically arranged flow passage structures at intervals along the length of the valveless micropump in the middle, namely a first external flow passage 610, a second external flow passage 620, and a third external flow passage 630. The resonant layer 500 has three internal flow passages 520 aligned with the first external flow passage 610, the second external flow passage 620, and the third external flow passage 630, respectively; the diameter of the internal flow passages 520 is smaller than the diameter of the corresponding external flow passages.

[0085] The diaphragm layer 300 and the resonant layer 500 are respectively provided with a first slit 310 and a second slit 510, consistent with those in Embodiment 1. A first diaphragm structure is formed between the two first slits 310. A second diaphragm structure is formed between the two second slits 510. The first diaphragm structure and the second diaphragm structure undergo opposite wave-like vibrations, forming three discontinuous flow-limiting points arranged sequentially in the pump chamber 700. The three discontinuous flow-limiting points are aligned with three internal flow-through holes 520, respectively; when the diaphragm layer 300 and the resonant layer 500 approach each other at the discontinuous flow-limiting points, the flow resistance of the corresponding internal flow-through holes 520 increases.

[0086] The working process of the valveless micropump based on parallel dual vibrators provided in this embodiment is as follows: a periodic electrical signal of a preset frequency is passed to the actuator 100, so that the diaphragm layer 300 and the resonant layer 500 vibrate in opposite directions, thereby realizing continuous pumping action.

[0087] Each vibration cycle of the actuator plate 100 is divided into a fluid intake process and a fluid output process.

[0088] like Figure 10As shown, in this embodiment, the fluid intake process is as follows: When the middle part of the actuator 100 vibrates upward through the piezoelectric effect, it drives the middle part of the reinforcing plate 200 to vibrate upward. The actuator 100 and the reinforcing plate 200 drive the middle part of the lower diaphragm layer 300 (corresponding to the second discontinuous flow limiting point) to vibrate upward. The middle part of the resonant layer 500 below the diaphragm layer 300 (corresponding to the second discontinuous flow limiting point) vibrates downward. At this time, the middle part of the pump chamber 700 (corresponding to the second discontinuous flow limiting point) vibrates downward. The volume of the diaphragm layer 300 increases; while the two sides below the diaphragm layer 300 (corresponding to the first and third discontinuous flow limiting points) bend downwards under the influence of the actuator plate 100 and the reinforcing plate 200, and the two sides of the resonant layer 500 (corresponding to the first and third discontinuous flow limiting points) bend upwards; the volume of the two sides of the pump chamber 700 (corresponding to the first and third discontinuous flow limiting points) decreases and the pressure increases; at the same time, the diaphragm layer 300 and the resonant layer 500 move closer to each other at the first and third discontinuous flow limiting points. At the same time, the diaphragm layer 300 and the resonant layer 500 move further apart at the corresponding second discontinuous flow limiting point, and the fluid flows into the middle of the pump chamber 700 from the outside through the second external flow passage 620 under the action of the pressure difference. At the same time, the external fluid at the top enters the two sides of the output chamber 800 through the flow holes on both sides of the valveless micropump and the first external flow passage 610 and the third external flow passage 610.

[0089] like Figure 11 As shown, in this embodiment, the fluid output process is as follows: When the middle part of the actuator plate 100 vibrates downward through the piezoelectric effect, it drives the middle part of the reinforcing plate 200 to vibrate downward. The middle parts of the actuator plate 100 and the reinforcing plate 200 drive the middle part of the diaphragm layer 300 below (corresponding to the second discontinuous flow limiting point) to vibrate downward. The middle part of the resonant layer 500 below the diaphragm layer 300 (corresponding to the second discontinuous flow limiting point) vibrates upward. At this time, the volume of the middle part (corresponding to the second discontinuous flow limiting point) in the pump chamber 700 decreases; while the two sides of the diaphragm layer 300... (Corresponding to the first and third discontinuous flow limiting points) bends upward under the action of the actuator plate 100 and the reinforcing plate 200 on both sides, and bends downward on both sides of the resonant layer 500 (corresponding to the first and third discontinuous flow limiting points); the volume of the two sides of the pump chamber 700 (corresponding to the first and third discontinuous flow limiting points) increases and the pressure decreases; at the same time, the diaphragm layer 300 and the resonant layer 500 approach each other at the second discontinuous flow limiting point, and the airflow in the middle of the output chamber 800 has difficulty entering the pump chamber 700, and is then output outward from the second external flow passage 620.

[0090] Example 3

[0091] This embodiment provides a valveless micropump with vertical air outlet based on parallel dual vibrators; the valveless micropump has a rectangular structure, with the width side extending in the front-to-back direction and the length side extending in the left-to-right direction.

[0092] This embodiment provides a valveless micropump based on parallel dual-vibrator plates, which is largely the same as that in Embodiment 3, except that: Figure 12 As shown, the rectifier layer 600 has a first external flow passage 610 only at its center. The resonant layer 500 has only one internal flow passage 520 aligned with the first external flow passage 610.

[0093] Each vibration cycle of the actuator plate 100 is divided into a fluid intake process and a fluid output process.

[0094] like Figure 13 As shown, in this embodiment, the fluid intake process is as follows: When the middle part of the actuator plate 100 vibrates downwards through the piezoelectric effect, it drives the middle part of the reinforcing plate 200 to vibrate downwards. The middle parts of the actuator plate 100 and the reinforcing plate 200 drive the middle part of the diaphragm layer 300 below to vibrate downwards, and the middle part of the resonant layer 500 vibrates upwards. Meanwhile, the two sides of the diaphragm layer 300 bend upwards under the influence of the two sides of the actuator plate 100 and the reinforcing plate 200, and the two sides of the resonant layer 500 bend downwards. During this process, external fluid enters the pump chamber and the output chamber through the first external flow hole 610 and the internal flow hole 520. At the same time, external fluid at the top enters the two sides of the output chamber through the flow holes on both sides of the valveless micropump.

[0095] like Figure 14 As shown, in this embodiment, the fluid output process is as follows: When the middle part of the actuator 100 vibrates upward through the piezoelectric effect, it drives the middle part of the reinforcing plate 200 to vibrate upward. The actuator 100 and the reinforcing plate 200 drive the middle part of the diaphragm layer 300 below to vibrate upward, and the middle part of the resonant layer 500 vibrates downward. Meanwhile, the two sides below the diaphragm layer 300 bend downward under the influence of the actuator 100 and the two sides of the reinforcing plate 200, and the two sides of the resonant layer 500 bend upward. During this process, the fluid in the pump chamber and the output chamber is output outward through the first external flow hole 610 and the internal flow hole 520. At the same time, the external fluid at the top continues to enter the two sides of the output chamber through the flow holes on both sides of the valveless micropump.

[0096] Compared to Example 2, this embodiment is more likely to produce greater noise.

[0097] Example 4

[0098] This embodiment provides a valveless micropump with vertical air outlet based on parallel dual vibrators; the valveless micropump has a rectangular structure, with the width side extending in the front-to-back direction and the length side extending in the left-to-right direction.

[0099] This embodiment provides a valveless micropump based on parallel dual-vibrator plates, which is largely the same as that in Embodiment 1, except that: Figure 15As shown, the flow channel layer 400 has only one parallel flow structure located in the middle.

[0100] In this embodiment, the valveless micropump draws in fluid when the middle of the actuator plate 100 vibrates downward and discharges fluid when the middle of the actuator plate 100 vibrates upward.

[0101] Example 5

[0102] like Figure 16 As shown, an array pumping structure includes multiple valveless micropumps arranged in a matrix or queue. The valveless micropumps are those provided in Embodiments 1, 2, 3, or 4. In this embodiment, there are eight valveless micropumps arranged in a 4×2 rectangle. In some other embodiments, the number and arrangement of the valveless micropumps are not limited, and other arrangement schemes besides 4×2 can be used, such as 2×1, 3×1, 4×1, and 2×2.

Claims

1. A valveless micropump based on parallel dual-vibrator plates, comprising a stacked vibrating element, a diaphragm layer (300), a flow channel layer (400), and a resonant layer (500); characterized in that: The opposite sides of the diaphragm layer (300) and the resonant layer (500) and the side wall of the groove in the flow channel layer (400) together form a pump chamber; the diaphragm layer (300) and the resonant layer (500) are both formed by two through gaps that are spaced apart to form a vibrating plate structure with fixed ends and free middle. The diaphragm structure corresponds to the pump chamber position; the vibrating element is used to drive the diaphragm layer (300) and the resonant layer (500) to perform synchronous and opposite wave-shaped vibrations; the vibrating diaphragm layer (300) and the resonant layer (500) periodically move away from and towards one or more discontinuous flow-limiting points; some or all of the discontinuous flow-limiting points are provided with flow passage structures that are connected to the external environment; the periodic movement of the diaphragm layer (300) and the resonant layer (500) away from and towards the discontinuous flow-limiting points causes the flow passage structures corresponding to the discontinuous flow-limiting points to periodically conduct and limit flow.

2. The valveless micropump according to claim 1, characterized in that: The two side edges of the diaphragm structure are aligned with the two side walls of the pump chamber, respectively.

3. The valveless micropump according to claim 1, characterized in that: Both the vibrating element and the diaphragm structure are rectangular; the vibrating element is fixed on the diaphragm structure of the diaphragm layer (300).

4. The valveless micropump according to claim 1, characterized in that: The number of discontinuous flow restriction points is three; the number of flow passage structures is one or three; the flow passage structures are located on the side of the flow channel layer (400); when the number of flow passage structures is one, the flow passage structure is aligned with the discontinuous flow restriction point located in the middle; when the number of flow passage structures is three, the three flow passage structures are aligned with the three discontinuous flow restriction points respectively.

5. The valveless micropump according to claim 4, characterized in that: The flow channel layer (400) has a fluid channel (460) on its side; the fluid channel (460) intersects with the flow structure in a cross shape; the diaphragm layer (300) has a plurality of flow holes (320) on its side; each flow hole (320) is connected to the fluid channel (460); each flow hole (320) is offset from the flow structure.

6. The valveless micropump according to claim 1, characterized in that: The diaphragm layer (300), flow channel layer (400) and resonant layer (500) are all provided with stress joints (900) surrounding the pump chamber.

7. The valveless micropump according to claim 1, characterized in that: It also includes a rectifier layer (600); the rectifier layer (600) is connected to the side of the resonant layer (500) away from the flow channel layer (400); the resonant layer (500) and the rectifier layer (600) are provided with one or more sets of mutually aligned through holes to form a flow structure that communicates with the external environment; the groove structure on the resonant layer (500) and the rectifier layer (600) together form an output chamber (800).

8. The valveless micropump according to claim 7, characterized in that: The two ends of the output chamber (800) are connected to the external environment through flow holes opened in the vibrating element, diaphragm layer (300) and flow channel layer (400).

9. The valveless micropump according to claim 1, characterized in that: The vibration element includes an actuating plate (100) and a reinforcing plate (200) stacked together.

10. A method for pumping air, characterized in that: The valveless micropump as described in claim 1 is used; the valveless micropump has three intermittent flow-limiting points; the pumping method includes: introducing a periodic electrical signal into the vibrating element to drive the diaphragm layer (300) and the resonant layer (500) to perform synchronous and opposite wave-shaped vibrations, with the intermittent flow-limiting points on both sides and the intermittent flow-limiting point in the middle alternately moving away from and towards each other; the flow passage structure corresponding to each intermittent flow-limiting point periodically draws air inward or pumps air outward.

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